BRPI0913405B1 - Method for glycosylating and separating plant fiber material - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a method for producing a saccharide including glucose by glycosylation of a plant fiber material and separation of the obtained saccharide. 2. Description of Related Art It has been suggested to produce a saccharide comprising mainly glucose or xylose from cellulose or hemicellulose by degradation of a plant material which is a biomass such as crushed sugarcane residues (bagasse). ) or wood chips, and effectively use the saccharide produced as food or fuel, and this process has been put into practice. In particular, attention has been drawn to a technology whereby a monosaccharide obtained by degradation of plant fibers is fermented to produce an alcohol, such as ethanol, as a fuel. A variety of methods for producing a saccharide such as glucose by degradation of cellulose or hemicellulose (e.g., Japanese Patent Application Publication No. 8-299000 (JP-A-8-299000) have been suggested above. Japanese Patent Application Publication No. 5 2006-149343 (JP-A-2006-149343), Japanese Patent Application Publication No. 2006-129735 (JP-A-2006-129735), and Patent Application Publication Japanese No. 2002-59118 (JP-A-2002-59118)). A typical method includes hydrolyzing the cellulose enzyme using sulfuric acid, such as dilute sulfuric acid or concentrated sulfuric acid or hydrochloric acid (JP-A-299000). A method is also available in which cellulase ( JP-A-2006-149343), a method in which a solid catalyst such as activated carbon or zeolite is used (JP-A-2006-129735), and a method in which pressurized hot water (JP However, a problem associated with the method by which cellulose is degraded by use of an acid such as sulfuric acid is that the acid that serves as a catalyst and the saccharide produced are difficult to Separate from the hydrolysis reaction mixture obtained by hydrolysis. This is because glucose, which is the major component of the cellulose hydrolysis product, and the acid that serves as a catalyst for hydrolysis, are both water soluble. Removal of acid by neutralization or ion exchange of the hydrolysis reaction mixture is not only difficult and expensive, but it is also difficult to remove acid completely and the acid often remains in the ethanol fermentation process. As a result, even when pH is optimized from the point of view of yeast activity in the fermentation process for ethanol, salt concentration increases, thereby reducing yeast activity and decreasing fermentation efficiency.

In particular, when concentrated sulfuric acid is used, sulfuric acid is very difficult to remove to such an extent that yeast is not deactivated in the ethanol fermentation process and such removal requires significant energy. In contrast, when dilute sulfuric acid is used, sulfuric acid is relatively easy to remove. However, it is necessary to degrade the cellulose under high temperature conditions, which is energy consuming. Yet another problem that arises when a concentrated sulfuric acid is used is that where the reaction is conducted for a long time, the saccharide produced is dehydrated and the saccharide yield decreases. As a result, even when a plant fiber material is added to the reaction system during hydrolysis to increase the amount of plant fiber material subjected to hydrolysis, the saccharide yield related to the plant fiber material does not increase. In addition, acid, such as sulfuric acid and hydrochloric acid, is very difficult to separate, collect, and reuse. Thus, the use of these acids as a catalyst to produce glucose is a cause of increased bioethanol cost.

With the method in which pressurized hot water is used, it is difficult to adjust conditions, and it is difficult to produce glucose in a stable yield. Also, in this method, even glucose is degraded, thereby reducing glucose yield. In addition, yeast activity is reduced by degraded components and fermentation may be inhibited. Another problem is associated with cost because the reactor (supercritical processing apparatus) is expensive and has poor durability.

SUMMARY OF THE INVENTION

The inventors conducted a comprehensive study of cellulose glycosylation and found that an acid grouped in a pseudofused state has excellent catalytic activity with respect to cellulose hydrolysis and can be easily separated from the saccharide produced. Patent applications covering the respective method have already been filed (Japanese Patent Application No. 2007-115407 and Japanese Patent Application No. 2007-230711). According to the present method, in contrast to the conventional method using concentrated sulfuric acid or dilute sulfuric acid, the hydrolysis catalyst can be recovered and reused and the process energy efficiency leading to the recovery of the aqueous saccharide solution and recovery of the Hydrolysis catalyst from cellulose hydrolysis can be increased. Furthermore, in the method of the aforementioned patent applications, the acid grouped in a pseudofused state acts as a catalyst for hydrolysis and also acts as a reaction solvent.

The inventors further promoted cellulose glycosylation screening using the pooled acid catalyst and successfully increased the processed amount of plant fiber material per unit weight of the pooled acid catalyst. Thus, the invention is based on the results obtained in the course of this research and provides a method for glycosylation and separation of a plant fiber material by using the acid catalyst grouped in a pseudofused state, wherein the processed amount of material fiber content per unit weight of the pooled acid catalyst is increased, the amount of pooled acid catalyst used is decreased, and energy efficiency is increased. The first aspect of the invention relates to a method for hydrolyzing a plant fiber material and producing and separating a saccharide, including glucose. This method includes a hydrolysis process of using a pseudofused grouped acid catalyst to hydrolyze the cellulose contained in the plant fiber material and produce glucose. In the hydrolysis process, the pooled acid catalyst and a first amount of the plant fiber material which increases a viscosity of the pooled acid catalyst in a pseudowinded state, when added to the pooled acid catalyst in a pseudowinded state, are heated and mixed, and a second amount of the vegetable fiber material is then additionally added when the viscosity decrease of a heated mixture of the pooled acid catalyst and the first amount of the vegetable fiber material occurs. The first quantity and the second quantity may be identical.

In Japanese Patent Application No. 2007-115407 and Japanese Patent Application No. 2007-230711, the inventors have disclosed a method for glycosylating and separating a plant fiber material, in which a pooled acid is heated to a pseudofused state and used. as a hydrolysis catalyst for plant fiber material. In this method of glycosylating and separating, the grouped acid in a pseudofused state acts as a hydrolysis catalyst and also acts as a reaction solvent for hydrolysis. For this reason, the mixing ratio of the pooled acid catalyst and the plant fiber material in the hydrolysis process is determined to ensure the miscibility of the pooled acid catalyst and the plant fiber material. In other words, the amount of plant fiber material that can be mixed in one cycle with the pooled acid catalyst is limited, and the processed amount of plant fiber material per unit weight of the pooled acid catalyst is also limited.

The results of the research conducted by the inventors demonstrated that in the method for glycosylating and separating a plant fiber material by using a pooled acid catalyst, where the plant fiber material is loaded in a plurality of cycles as described above, when the pooled acid catalyst and the plant fiber material is stirred under heating and the plant fiber material is hydrolyzed, the amount processed for the plant fiber material by unit weight of the pooled acid catalyst is increased. Thus, initially, the pooled acid catalyst and the amount of plant fiber material that is added to increase viscosity are heated and mixed and hydrolysis of the plant fiber material is initiated. Then, when the viscosity of the heated mixture in which the vegetable fiber material has been hydrolyzed is decreased, the vegetable fiber material is additionally added. Thus, it has been found that the heated mixture of the acid catalyst grouped in a pseudofused state and the vegetable fiber material has a high viscosity in the initial stage of the hydrolysis reaction, but the viscosity decreases as the hydrolysis of the fiber material. vegetable progresses. In addition, it has been found that because of the decreased viscosity of the heated mixture, even when the vegetable fiber material is refilled into the heated mixture, the heated mixture can still be mixed and stirred and both the initially charged vegetable fiber material. when the additionally added vegetable fiber material can be hydrolyzed, while ensuring a high sa-carid yield. In other words, according to the invention, the processed amount of the vegetable fiber material may be increased by the amount of vegetable fiber material which is additionally added compared to the conventional one. As a result, the processed amount of the vegetable fiber material per unit weight of the pooled acid catalyst is increased and a cost reducing effect on saccharide production is obtained due to the decrease in the amount of pooled acid catalyst used. Furthermore, because the vegetable fiber material is additionally added to the heated mixture in the catalyst process including the grouped acid catalyst in a pseudofused state, the energy required for heating that is required to obtain the pseudofused state of the bundled acid catalyst can be decreased. Thus, energy efficiency can be increased. The degree of viscosity reduction of the heated mixture into which the vegetable fiber material is additionally added may be suitably determined according to the amount of the vegetable fiber material to be additionally added. Thus, where a small amount is to be added additionally, it may be charged after a relatively small decrease in viscosity, but where a large amount is to be loaded, the vegetable fiber material is not added until the hydrolysis reaction progresses. sufficiently and the viscosity decreases significantly. In any case, it is preferred that the plant fiber material be added further so as not to exceed the viscosity obtained after the initial addition of the fiber material.

As an indicator of the period when the second amount of the vegetable fiber material is to be additionally added may be, for example, a time when the viscosity of the heated mixture decreases to or below 1.5 Pa.s (1500 cp). .

A volume ratio of the first amount of the vegetable fiber material to the pooled acid catalyst may be equal to or greater than 60%. A volume ratio of the amount of plant fiber material that is then added to the pooled acid catalyst may be equal to or greater than 60%.

According to the invention, in the method for glycosylating and separating a plant fiber material using a pooled acid catalyst in a pseudofused state, it is possible to increase the hydrolyzed amount of the plant fiber material per unit weight of the pooled acid catalyst. , decrease the amount of grouped acid used, and increase energy efficiency. Therefore, according to the invention, the cost and energy consumption of saccharide production by hydrolysis of a plant fiber material can be reduced. The second aspect of the invention relates to a method for hydrolyzing a plant fiber material and producing and separating a saccharide, including glucose. The method includes a hydrolysis process of utilizing an acid catalyst grouped in a pseudo-fused state to hydrolyze the cellulose contained in the plant fiber material and produce glucose. In the hydrolysis process, the vegetable fiber material is added when a viscosity of a pooled acid catalyst mixture and the vegetable fiber material becomes a first predetermined value, and then the addition of the vegetable fiber material is stopped when The viscosity of the mixture becomes a second predetermined value that is greater than the first predetermined value.

BRIEF DESCRIPTION OF DRAWINGS

The foregoing and additional objects, features and advantages of the invention will become apparent from the following description of the illustrative embodiments with reference to the accompanying drawings, where like numerals are used to represent like elements and where: FIG. . 1 shows a Keggin structure of a heteropoly acid; FIG. 2 is a graph showing a relationship between the crystallization water ratio in a pooled acid catalyst and the apparent melt temperature: FIG. 3 is a schematic diagram illustrating one embodiment of a batch type reaction device that may be used in a hydrolysis process; and FIG. 4 is a schematic diagram of a bypass reaction apparatus that is used in the hydrolysis process of Example 3.

DETAILED DESCRIPTION OF MODALITIES

A method for glycosylating and separating a plant fiber material which is an embodiment of the invention will be described below. First, a hydrolysis process will be described, in which the cellulose contained in the plant fiber material is hydrolyzed and a saccharide, which includes mainly glucose, is produced. In the explanation below, attention is focused on the process in which glucose is mainly produced from cellulose, but a process in which hemicellulose is included, in addition to cellulose, in plant fiber material and a process in which the product includes Other monosaccharides such as xylose in addition to glucose also fall within the scope of the invention. Vegetable fiber material is not particularly limited as long as it includes cellulose or hemicellulose, and examples include cellulose-based biomass such as broad-leaved trees, bamboos, coniferous trees, "kenaf". ", furniture scrap wood, rice straws, wheat straws, rice husks, and crushed sugar cane residues (bagasse). The plant fiber material may be cellulose or hemicellulose that is separated from biomass, or it may be cellulose or hemicellulose that is artificially synthesized. Such fiber materials are commonly used in pulverized form to improve dispersibility in the reaction system. The spray method may be a commonly used method. From the point of view of facilitating mixing with the pooled acid catalyst and reaction, it is preferred that the vegetable fiber material is sprayed to a powder with a diameter of about a few microns to 200 μίτι. The lignin contained in the fiber material may be dissolved, if necessary, by pulping treatment in advance. The amount of residue during glycosylation and separation may be reduced by dissolving and removing the lignin, the produced saccharide or the grouped acid may be prevented from mixing with the residue, and the reduction in saccharide yield or recovery ratio of lignin. pooled acid can be inhibited. In a case where pulping treatment is carried out, the degree of grinding of the vegetable fiber material may be comparatively small (coarse grinding). The resultant effect is that the labor, cost, and energy required to spray the fiber material can be reduced. Pulping treatment may be effected, for example, by placing the vegetable fiber material (e.g. from several centimeters to several millimeters) in contact with an alkali or salt such as NaOH, KOH, Ca (OH ) 2, Na2 SO3, NaH-CO3, NaHS03, Mg (HS03) 2, Ca (HS03) 2, an aqueous solution of them, a mixture of them with a solution of SO2, or a gas such as NH3 under steam. Specific conditions include a reaction temperature of 120 to 160 ° C and a reaction time of several dozen minutes to about 1 h.

In accordance with the invention, pooled acid, used as a catalyst for hydrolyzing plant fiber material, means an acid in which a plurality of oxo acids, i.e. a so-called polyacid, is condensed. In most polyacids, a plurality of oxygen atoms are attached to a central element. As a result, polyacids are known to be primarily in a state of oxidation to the maximum oxidation number, demonstrate excellent properties as an oxidation catalyst, and are strong acids. For example, the acid strength of phosphotungstic acid (pKa = -13.16), which is a heteropoly acid, is greater than the acid force of sulfuric acid (pKa = -11.93). Thus, even under mild temperature conditions, such as a temperature of 50 ° C, for example, it is possible to degrade cellulose or hemicellulose to produce a monosaccharide such as glucose or xylose. The grouped acid used in the invention may be a homopoly acid or a heteropoly acid, but a heteropoly acid is preferred because it has a high oxidizing capacity and a high acid strength. The heteropoly acid that can be used is not particularly limited. For example, the heteropolyacid may be represented by the general formula HwAxB-yOz (A means a heteroatom, B means a polyatom that serves as a polyacid backbone, w means a hydrogen atoms composition ratio, x means a atoms composition ratio). heteroatoms, y means a polyatom composition ratio, and z means an oxygen atom composition ratio). Examples of polyatom B include atoms such as W, Mo, V, and Nb, which may form the polyacid. Examples of heteroatom A include atoms such as P, Si, Ge, As, and B which may form a heteropoly acid. The number of types of polyatoms and heteroatoms that are contained in a single heteropoly acid molecule can be one or more.

Because of the good balance of acid strength and oxidizing capacity, it is preferred that phosphotungstic acid H3 [PWi2O40] or silicotungstic acid H4 [SiW12O40], which are tungstates, be used. Phosphomolybdic acid H3 [PMo1204o], which is a molybdate, may also be advantageously used. The structure of a Keggin type heteropoly acid [Χπ + Μ12Ο40: X = P, Si, Ge, As, etc., M = Mo, W, etc.] (phosphotungstic acid) is shown in FIG. 1. An X04 tetrahedron is present in the center of a polyhedron consisting of octahedral unidadesβ units, and large amount of crystallization water is present around this structure. The structure of the grouped acid is not particularly limited and may be not only of the Keggin type, but also, for example, of a Dawson type. Here, water that is hydrated or coordinated to the grouped acid catalyst in a crystalline state or the grouped acid catalyst consisting of several molecules of the grouped acid catalyst is described by a commonly used term "crystallization water". Crystallization water includes the water anion which is hydrogen bonded to the anion constituting the pooled acid catalyst, the coordinating water that is coordinated to the cation, the crystal lattice water that is not coordinated to the cation or anion, and also water that is contained in the form of OH groups. The grouped acid catalyst in a grouped state in an association consisting of one to several grouped acid molecules and is different from a crystal. The grouped acid catalyst in a grouped state may be in a solid state, a pseudofused state, and a dissolving state in a solvent (colloidal state).

In the hydrolysis process of the glycosylate and separation method according to the invention, the vegetable fiber material is divided and added in cycles. Therefore, monosaccharide that was produced from the plant fiber material that was loaded at the beginning of the hydrolysis process is heated and continuously mixed with the acid catalyst grouped together with the additionally loaded plant fiber material. Therefore, the occurrence of monosaccharide dehydration reaction (hyperreaction) is inhibited, thereby making it possible to increase monosaccharide yield. From this point of view, it is preferred that a catalyst in a pooled state having an acid force suitable for cellulose hydrolysis as the pooled acid catalyst is used. Because a grouped acid in a grouped state hardly induces monosaccharide overreaction, the yield of monosaccharides does not decrease, even on long-term heating of the acid grouped with the monosaccharide. A method for preparing the pooled acid catalyst in a pooled state is not particularly limited. A specific method for this will be described below. The grouped acid catalyst described above is in a solid state at normal temperature, but becomes a pseudofused state when heated to a higher temperature. The pseudofused state, as referred to herein, means a state in which the pooled acid is apparently fused but not completely fused to a liquid state; The pseudo-fused state is similar to a colloidal (sol) state, in which the pooled acid is dispersed in a liquid, and is a state in which the pooled acid shows fluidity. It can be confirmed whether the clustered acid is in the pseudofused state by visual observations, or in the case of a homogeneous system by DTG (Differential Scanning Calorimetry). The pseudofused state of the pooled acid changes depending on the temperature and amount of crystallization water contained in the pooled acid catalyst (see FIG. 2). More specifically, where the amount of crystallization water contained in the phosphotungstic acid, which is a pooled acid, is high, the temperature at which the acid shows a pseudofused state decreases. Thus, a pooled acid catalyst containing a large amount of crystallization water demonstrates a catalytic effect on the cellulose hydrolysis reaction at a lower temperature than that of a pooled acid catalyst with a relatively small amount of crystallization water. In other words, by controlling the amount of crystallization water contained in the pooled acid catalyst in the hydrolysis process reaction system, it is possible to bring the pooled acid catalyst to a pseudofused state at the target hydrolysis reaction temperature. For example, when phosphotungstic acid is used as the pooled acid catalyst, it is possible to control the hydrolysis reaction temperature within the range of 40 to 110 ° C by changing the amount of crystallization water in the pooled acid (see FIG. 2), FIG. 2 shows a relationship between the ratio of water of crystallization in heteropoly acid (phosphotungstic acid), which is a typical pooled acid catalyst, and the temperature (apparent melting temperature) at which the pseudofused state is first demonstrated. The grouped acid catalyst is in a solid state in the region below the curve, and in a pseudofused state in the region above the curve. Furthermore, in FIG. 2, the crystallization water ratio (%) is a value obtained assuming that a standard amount of crystallization water n (n = 30) in the pooled acid (phosphotungstic acid) is 100%. Because no component of the grouped acid catalyst is thermally decomposed and volatilized, even at a high temperature, such as 800 ° C, the amount of crystallization water can be specified by a pyrolytic method (TG measurements). The standard amount of crystallization water, as referred to herein, is the amount (the number of molecules) of crystallization water contained in a molecule of acid grouped in a solid state at room temperature, and the standard amount varies depending on the type. of grouped acid. For example, the standard amount of crystallization water is about 30 in phosphotungstic acid (H3 [PWi204o] nH20 (n '30)), about 24 in silicotungstic acid (H4SÍW12O40] nH20 (n' 24)), and about 30 in phosphomolibidic acid (Η3 [ΡΜθι2θ4ο] nH20 (n * 30)). The amount of crystallization water contained in the pooled acid catalyst can be regulated by controlling the amount of water present in the hydrolysis reaction system. Specifically, when it is desired to increase the amount of crystallization water contained in the pooled acid catalyst, ie to decrease the reaction temperature, it is possible to add water to the hydrolysis reaction system by adding water to the fiber material mixture. and the grouped acid catalyst or by increasing the relative humidity of the reaction system atmosphere. As a result, the pooled acid receives the added water as crystallization water, and the apparent melting temperature of the pooled acid catalyst is decreased.

In contrast, when it is desired to reduce the amount of crystallization water contained in the pooled acid catalyst, ie, to increase the reaction temperature, it is possible to reduce the amount of crystallization water contained in the pooled acid catalyst by removing water from the system. hydrolysis reaction, for example by heating the reaction system to evaporate water, or by adding a desiccant to the mixture containing the plant fiber material and the grouped acid catalyst. As a result, the apparent melting temperature of the pooled acid catalyst is high. As described above, it is possible to easily control the amount of crystallization water contained in the pooled acid, and it is also possible to easily regulate the reaction temperature at which the cellulose is hydrolyzed by controlling the amount of crystallization water.

As described above, the grouped acid exhibits a high catalytic activity for cellulose hydrolysis even at low temperatures due to a high acid strength of the grouped acid. Because the diameter of a pooled acid molecule is about 1 to 2 nm, typically slightly larger than 1 nm, the pooled acid is easily mixed with the plant fiber material, which is the raw material, and therefore promotes hydrolysis of cellulose efficiently. Thus, it is possible to hydrolyze the cellulose under mild temperature conditions with high energy efficiency and low environmental load. Moreover, in contrast to the conventional method for cellulose hydrolysis, which uses an acid such as sulfuric acid, the method according to the invention which uses a grouped acid as a catalyst, the separation efficiency of the saccharide and the Catalyst is high and they can be easily separated. Because the grouped acid is in a solid state at a certain temperature, it can be separated from the saccharide, which is the product. Therefore, the separated grouped acid can be recovered and reused. Furthermore, because the acid catalyst grouped in a pseudofused state also acts as a reaction catalyst, the amount of solvent used as the reaction solvent can be greatly reduced compared to that of the conventional method. This means that separation of the grouped acid and saccharide, which is the product, and recovery of the grouped acid can be accomplished at increased efficiency. Thus, the invention in which Î ± -grouped acid is used as the cellulose hydrolysis catalyst can reduce the cost and decrease the environmental burden.

According to the invention, in the hydrolysis process in which a plant fiber material is hydrolyzed and a saccharide is produced using a pseudofused grouped acid catalyst, the grouped acid catalyst and an amount of the plant fiber material , which increases the viscosity of the grouped acid catalyst in a pseudo state when added to the grouped acid catalyst in a pseudo state, are heated and mixed, thereby promoting hydrolysis of the plant fiber material, and the plant fiber material is then added. further charged at-post the viscosity of the heated mixture has decreased.

In this case, the amount of plant fiber material that increases a viscosity of the acid catalyst grouped in a pseudofused state, when added to the acid catalyst grouped in a pseudofused state, as referred to herein, is the amount that increases the viscosity when the Clustered acid catalyst used in the hydrolysis process is in a pseudo-fused state and the plant fiber material is added to the clustered acid catalyst in a pseudo-fused state, on the viscosity of the clustered acid catalyst in a pseudo-fused state, prior to the addition of material of vegetable fiber. The specific amount of the vegetable fiber material differs depending on the properties of the vegetable fiber material used (size, shape, pore structure, and the like) and heating temperature, agitation (kneading) state, and temperature distribution during the mixture of the acid catalyst plant fiber material grouped in a pseudofused state and the plant fiber material. Therefore, the specific amount may be appropriately determined in advance. Normally, where the volume ratio of the vegetable fiber material to the grouped acid catalyst used in the hydrolysis process is equal to or greater than 60%, the viscosity increases when the vegetable fiber material is added. to the acid catalyst grouped in a pseudofused state. In particular, from the point of view of the processing efficiency of the vegetable fiber material, it is preferred that the volume ratio of the vegetable fiber material to the grouped acid catalyst used in the hydrolysis process be equal to or greater than that, 50%, even more preferably equal to or greater than 65%. The sequence in which the pooled acid catalyst and plant fiber material is loaded into a reaction vessel is not particularly limited. For example, the pooled acid catalyst may be charged and heated to a pseudofused state, and then the plant fiber material may be charged. Alternatively, the pooled acid catalyst and plant fiber material may be loaded together and then heated to bring the pooled acid catalyst to a pseudofused state. In a case where the pooled acid catalyst and the vegetable fiber material is heated after loading, the pooled acid catalyst and the vegetable fiber material is preferably mixed and shaken in advance prior to heating. The degree of contact between the grouped acid and the plant fiber material may be increased by conducting the mixture to some degree before the grouped acid is brought to a pseudofused state.

As described above, because the pooled acid catalyst becomes a pseudofused state and acts as a reaction catalyst in the hydrolysis process according to the invention, no water or organic solvent can be used as a reaction solvent. In the hydrolysis process, however, water or organic solvent may be required depending on the shape (size, fiber state, etc.) of the plant fiber material, the mixing ratio and the volume ratio of the pooled acid catalyst and vegetable fiber material, and the like. However, water is required to hydrolyze cellulose in the hydrolysis process. More specifically, (n-1) water molecules are required to degrade cellulose, where (n) glycoses have been polymerized to (n) glycoses (n is a natural number). Therefore, in a case where a sum total of the amount of crystallization water that is required to bring the pooled acid to a pseudofused state at the reaction temperature and the amount of water required to hydrolyze the entire charged amount of cellulose to glucose If not present in the reaction system, the pooled acid catalyst crystallization water is used for cellulose hydrolysis, the amount of the pooled acid catalyst crystallization water decreases, and the pooled acid solidifies. Thus, the degree of contact between the pooled acid catalyst and the plant fiber material or the viscosity of the blend of the plant fiber material and the pooled acid catalyst is increased and a long time is required to mix the mixture sufficiently.

Therefore, to ensure the catalytic action of the pooled acid catalyst and its function as a reaction solvent at the reaction temperature in the hydrolysis process, ie to enable the pooled acid catalyst to maintain the pseudofused state, it prefers It is believed that the amount of water in the reaction system satisfies the following condition. Thus, it is preferred that the amount of water in the reaction system be equal to or greater than the sum of the (A) amount of crystallization water required for the entire pooled acid catalyst present in the reaction system. being in the pseudo-molten state at the reaction temperature in the hydrolysis process, and (B) the amount of water required for the entire amount of cellulose present in the reaction system to be hydrolyzed to glucose. It is especially preferred that the sum total of (A) and (B) be added. This is because where extra water is added, the produced saccharide and the pooled acid are dissolved in the extra water and a process of separating the saccharide and the pooled acid becomes difficult. Prior to the additional loading of the additionally loaded vegetable fiber material, the amount (B) of water is the amount (B1) of water that is required to hydrolyze to glucose the entire amount of cellulose contained in the vegetable fiber material that is hydrolyzed. and after additional loading of the vegetable fiber material, the amount (B) of water is the amount (B1 + B2) that is required to hydrolyze to glucose the entire amount of cellulose contained in the vegetable fiber material that is hydrolyzed. additionally and in the subsequently added vegetable fiber material. As for the amount (B) of water, the total amount (B1 + B2) may be added before additional loading of the vegetable fiber material, or B1 and B2 may be added separately, corresponding to the additional loading of the fiber material. vegetable.

In the hydrolysis process, the amount of water in the reaction system decreases and the amount of crystallization water of the pooled acid catalyst also decreases. As a result, the pooled acid catalyst may become solid and the degree of contact with the vegetable fiber material and the mixing ability of the reaction system may degrade. The occurrence of such problems can be prevented by increasing the hydrolysis temperature so that the pooled acid catalyst is brought to the pseudo-molten state. Furthermore, it is preferred that the desired amount of crystallization water from the pooled acid catalyst can be ensured even when the relative humidity of the reaction system is decreased by heating in the hydrolysis process. Specifically, a method may be used whereby a saturated vapor pressure state is produced at the hydrolysis reaction temperature within a pre-sealed reaction vessel such that the atmosphere of the reaction system at a reaction temperature predetermined, is below the saturated vapor pressure, the temperature is lowered to condense the steam while maintaining the sealed state, and the condensed water is added to the plant fiber material and the bundled acid catalyst. In addition, in a case where moisture-containing plant fiber material is used, it is preferred that the amount of moisture contained in the plant fiber material is also considered as the amount of moisture present in the reaction system; This is not particularly necessary in a case where dry vegetable fiber material is used.

When the hydrolysis reaction of the vegetable fiber material has progressed and the viscosity of the heated mixture has decreased, the vegetable fiber material is further charged. The viscosity of the heated mixture may be measured directly with a viscometer (eg, a shear sound resonator or the like) disposed within the reaction vessel, or determined indirectly from the torque of the stirring paddle mixing the heated mixture. , the height of the liquid measured by the liquid level meter disposed within the reaction vessel, and the ratio between the rotation and torque of the stirring blade. The viscosity of the heated mixture at the time the vegetable fiber material is additionally loaded is not limited to a specific value as long as it is less than the viscosity of the heated mixture which includes the pseudofused grouped acid catalyst and vegetable fiber material in the early stage of the hydrolysis process reaction and the heated mixture may be mixed despite the additional loading of the vegetable fiber material into the heated mixture. The viscosity of the heated mixture into which the vegetable fiber material is to be additionally loaded may be suitably determined corresponding to the amount of the vegetable fiber material that will be additionally loaded. Thus, where a small amount is to be additionally charged, the additional loading may be performed when the viscosity has decreased slightly, and where a large amount is to be further charged, the additional loading is performed after waiting until the hydrolysis reaction progresses. sufficiently and the viscosity decreases significantly. In any case, it is preferred that the additional loading be carried out so as not to exceed the viscosity of the heated mixture at the initial reaction stage when the fiber material is initially added. Typically, it is preferred that the vegetable fiber material be further loaded after the viscosity of the heated mixture has decreased to or below 1.5 Pa.s (1500 cp), preferably equal to or below 1.2 Pa.s. Pa.s (1200 cp), and even more preferably equal to or below 1 Pa.s (1000 cp). The amount of the vegetable fiber material that is additionally loaded is not particularly limited and can be appropriately determined as long as it is within a range in which the mixing ability of the heated mixture upon further loading of the vegetable fiber material can be achieved. be assured. From the point of view of the processing efficiency of the vegetable fiber material, it is generally preferred that the volume ratio of the subsequently added vegetable fiber material to the pooled acid catalyst that is used in the hydrolysis process is equal to, or greater than 60%. Additional loading of the vegetable fiber material may be effected in a plurality of cycles. Thus, it is possible to repeat a process in which the vegetable fiber material is further charged after the viscosity of the heated mixture has decreased after the previous further loading of the vegetable fiber material. Additional loading of the fiber material into the hydrolysis process can be easily controlled by feedback feedback variations in the viscosity of the heated mixture, which are measured by the viscometer, stirring blade torque, liquid level meter, or the like above. described for the mechanism for loading the vegetable fiber material and further loading the vegetable fiber material into the heated mixture when the viscosity of the heated mixture decreases. More specifically, for example, in a case of a fixed (batch type) reaction apparatus shown in FIG. 3, the viscosity of a heated mixture 4 located in a reaction vessel 1 may be measured with a viscosity sensor 2 and liquid level sensor 3. The viscosity sensor 2, which measures the viscosity of the heated mixture 4, is preferably arranged on the bottom surface of the reaction vessel 1 or in a position close to the bottom surface on the side. Moreover, where a plurality of liquid level sensors 3 are disposed on the side surface of the reaction vessel 1, the variations in the liquid level of the heated mixture 4 within the reaction vessel 1 can be precisely measured. In this case, by supplying a plurality of temperature sensors 5 together with the liquid level sensors 3, it is possible to carry out proper feedback control of the rotation speed of the stirring blade (see FIG. 3). As described above, the changes in viscosity of the heated mixture 4 that are measured with the viscosity sensor 2 and the liquid level sensor 3 are preferably returned by feedback to a vegetable fiber material loading mechanism 9. In the arrangement shown in FIG. 3, a heating heater 7 and a temperature sensor 8 are arranged on the bottom surface of the reaction vessel 1, and the temperature of the heated mixture 4 located in the reaction vessel 1 can be controlled. In addition, the configuration of the fixed (batch type) reaction apparatus is not limited to that shown in FIG. 3. For example, as described above, the viscosity of the heated mixture 4 may be measured indirectly from the stirring blade torque 6. FIG. 4 shows one embodiment of a bypass reaction apparatus. In a cylindrical reaction vessel 100 having a stirring mechanism (a stirring paddle 10) shown in FIG. 4, a plurality of loading holes 11 (1) to 11 (4) for the vegetable fiber material and viscosity sensors 12 (1) to 12 (4) are arranged in the downstream direction of a loading hole. 13 for the pseudofused grouped acid catalyst. The additional loading period or additionally loaded amount of the vegetable fiber material to be loaded from the loading holes 11 can be determined from the heated moisture viscosity which is measured by the downstream viscosity sensor 12 to the positions where loading holes 11 are disposed. In this case, the reaction can be easily controlled in the hydrolysis process by feedback feedback of the heated mixture viscosity, which is measured with the viscosity sensors 12, for the additional loading period or the additionally loaded amount of the vegetable fiber material. which will be further loaded from loading holes 11. The arrangement positions of the viscosity sensors 12 and loading holes 11 are not particularly limited. For example, the viscosity sensor 12 (1) may be arranged adjacent to and upstream of the loading hole 11 (2), which is arranged downstream of the loading hole 11 (1) (see FIG. 4). . Loading holes 11 (2) and 11 (3) and viscosity sensors 12 (2) and 12 (3) are similarly arranged. In a through-flow reaction apparatus, in a case where a lignin-containing plant fiber material is used, a heteropoly acid or saccharide produced is not removed immediately prior to the loading holes 11, but the upstream residue is preferably removed disposing of it. a filter that can remove lignin. The advantage of lowering the reaction temperature in the hydrolysis process is that energy efficiency can be increased. The selectivity of glucose production in the hydrolysis of cellulose contained in the plant fiber material varies depending on the hydrolysis process. The efficiency of the reaction generally increases as the reaction temperature rises. For example, as described in Japanese Patent Application No. 2007-115407, in the cellulose hydrolysis reaction using phosphotungstic acid with a crystallization water ratio of 160%, the reaction rate R at a temperature of 50 to 90 ° C. it rises with increasing temperature and almost the entire cellulose reacts around 80 ° C. Glucose yield shows a similar tendency to increase by 50 to 60 ° C, peaks at 70 ° C and then decreases. Thus, glucose is produced with high selectivity at 50 to 60 ° C, but at 70 to 90 ° C, reactions other than glucose production, such as the production of other saccharides such as xylose, and formation also occur. of decomposition products. Therefore, the hydrolysis reaction temperature is an important factor governing cellulose reaction rate selectivity and glucose production selectivity, and it is preferable that the hydrolysis reaction temperature be low in view of energy efficiency. However, it is preferred that the temperature of the hydrolysis reaction be determined by taking also into account the cellulose reaction rate and the selectivity of glucose production.

As described above, the temperature conditions in the hydrolysis process may be suitably determined with consideration for a number of factors (eg, reaction selectivity, energy efficiency, cellulose reaction rate, etc.), however, From the standpoint of the balance of energy efficiency, cellulose reaction rate, and glucose yield, the temperature is usually preferred at or below 140 ° C, and the temperature is especially preferred. equal to or less than 120 ° C. Depending on the shape of the vegetable fiber material, a low temperature of equal to or less than 100 ° C may also be used. In this case, glucose can be produced with especially high energy efficiency. The pressure in the hydrolysis process is not particularly limited, however, because the catalytic activity of the grouped acid catalyst relative to the cellulose hydrolysis reaction is high, cellulose hydrolysis can be promoted with good efficiency even under mild pressure conditions. , such as a range from normal pressure (atmospheric pressure) to 1 MPa.

Because the mixture which includes the pooled acid catalyst and the vegetable fiber material in the hydrolysis process has a high viscosity, for example, a ball mill using heating can be advantageously used, but a typical stirring device can also be used. The duration of the hydrolysis process is not particularly limited and may be appropriately defined according to the shape of the plant fiber material used, the ratio of the plant fiber material and the pooled acid catalyst, the catalytic activity of the pooled acid catalyst, reaction temperature, reaction pressure, and the like.

Where the temperature of the reaction system decreases after the end of hydrolysis is decreased, the saccharide produced in the hydrolysis process becomes an aqueous saccharide solution where water, which dissolved the saccharide, is present in the reaction mixture. hydrolysis including the pooled acid catalyst, and where no water is present, the saccharide precipitates and is contained in the solid state. Part of the saccharide produced may be present as an aqueous solution and the balance may be contained as a solid state mixture. Because the pooled acid catalyst is also water soluble, where a sufficient amount of water is contained in the mixture after the hydrolysis process, the pooled acid catalyst is also dissolved in water.

A saccharide separation process in which the saccharide (including mainly glucose) produced in the hydrolysis process and the grouped acid catalyst are separated will be described below. In the glycosylation and separation method according to the invention, a method for separating saccharide and grouped acid is not limited to the method described below. The reaction mixture after the hydrolysis process (may also be referred to below as the "hydrolysis reaction mixture") includes at least the grouped acid catalyst and the produced saccharide. In a case where the amount of water in the hydrolysis process is a total of the sum of (A) and (B), the saccharide of the hydrolysis reaction mixture precipitates. In the meantime, the grouped acid catalyst also becomes a solid state as the temperature decreases. Depending on the type of plant fiber material used, a residue (unreacted cellulose or lignin, etc.) is contained as a solid component in the hydrolysis reaction mixture. The pooled acid catalyst shows solubility in organic solvents, in which the saccharide comprising mainly glucose is insoluble or has unsatisfactory solubility. Therefore, it is possible to add an organic solvent that is a weak solvent for the saccharide and a good solvent for the pooled acid catalyst to the hydrolysis reaction mixture, stir, selectively dissolve the pooled acid catalyst in the organic solvent, and then separate the organic solvent solution containing the grouped acids and a solid component including the saccharide by solid-liquid separation. Depending on the plant fiber material used, a residue or the like may be contained in the solid component that includes the saccharide. A method for separating the organic solvent solution and the solid component is not particularly limited, and a typical solid-liquid separation method, such as decantation and filtration, may be used. The organic solvent is not particularly limited as long as it is a good solvent for the clustered acid catalyst and a weak saccharide solvent, however, to prevent dissolution of the saccharide in the organic solvent, it is preferred that the solubility of the saccharide in the organic solvent is equal to or less than 0.6 g / 100 ml, and more preferably equal to or less than 0.06 g / 100 ml. In this case, to increase the recovery ratio of the pooled acid catalyst, it is preferred that the pooled acid solubility in the organic solvent is equal to or greater than 20 g / 100 ml, more preferably equal to or greater than which 40 g / 100 ml.

Specific examples of the organic solvent include alcohols, such as ethanol, methanol, n-propanol, and octanol, and ethers, such as diethyl ether and di-sopropyl ether. Alcohols and ethers may be advantageously used, and among them, from the point of view of dissolution capacity and boiling point, ethanol and diethyl ether are preferred. Diethyl ether does not dissolve saccharides, such as glucose, and has a high ability to dissolve grouped acids. Therefore, diethyl ether is one of the ideal solvents for separating saccharides and grouped acid catalysts. Ethanol also poorly dissolves saccharides, such as glucose, and has a high ability to dissolve clustered acids. Therefore, it is also one of the ideal solvents. Diethyl ether is superior to ethanol in terms of distillation, but the advantage of ethanol is that it is easier to obtain than diethyl ether. The amount of organic solvent differs depending on the ability of the solvent to dissolve the saccharide and grouped acid catalyst and the amount of moisture contained in the hydrolysis reaction mixture. Therefore, the appropriate amount of organic solvent can be appropriately determined.

It is generally preferred that stirring of the hydrolysis reaction mixture and the organic solvent is carried out within a temperature range from room temperature to 60 ° C, the specific temperature depending on the boiling point of the organic solvent. The stirring method of the hydrolysis reaction mixture and the organic solvent is not particularly limited and stirring may be effected by a typical method. From the point of view of recovery efficiency of the grouped acid, agitation and milling with a ball mill are preferred as the stirring method.

To increase the recovery ratio of saccharide and grouped acid and increase the purity of the obtained saccharide, it is preferred that the organic solvent (the organic solvent which is a weak saccharide solvent and a good solvent for the grouped acid catalyst) It is added to and stirred with the solid component obtained by the solid-liquid separation mentioned above, thereby washing with the organic solvent. This is because the pooled acid catalyst that had been mixed with the solid component can be removed and recovered. A mixture in which the organic solvent is added to the solid component may be separated into the solid component and the organic solvent solution including the acid grouped by solid-liquid separation in the same manner as in the hydrolysis reaction mixture. If necessary, the solid component may be washed with the organic solvent a plurality of times. Adding water, such as distilled water, to the solid component obtained by separating solid-liquid with water, stirring and then solid-liquid separation (because the saccharide is water soluble) It is possible to separate the aqueous saccharide solution from the solid component including the residue or the like.

By removing the organic solvent from the liquid component (organic solvent solution including the pooled acid catalyst dissolved therein) obtained by solid-liquid separation, it is possible to separate the pooled acid catalyst and the organic solvent and recover the pooled acid catalyst. . One method for removing organic solvent is not particularly limited. Examples of suitable methods include vacuum distillation, lyophilization, and evaporative drying. Among them, vacuum distillation is preferred at a temperature of equal to or less than 50 ° C. The recovered pooled acid catalyst may again be used as the hydrolysis catalyst for the plant fiber material. The organic solvent solution including the pooled acid recovered after washing the solid component obtained by the aforementioned solid-liquid separation can be used again to wash the organic component.

Depending on the amount of moisture in the hydrolysis process, the hydrolysis reaction mixture may contain an aqueous solution that includes the saccharide and the grouped acid dissolved in it. In this case, the solid component including the saccharide and the organic solvent including the pooled acid catalyst dissolved therein may be separated by removing moisture from the hydrolysis reaction mixture to precipitate the dissolved saccharide and pooled acid and then adding the dissolved organic solvent, stirring and effecting of the grouped acid and then addition of organic solvent, stirring and effecting solid-liquid separation. It is especially preferred that the amount of moisture in the hydrolysis reaction mixture is adjusted so that the ratio of crystallization water in the entire pooled acid catalyst contained in the hydrolysis reaction mixture is less than 100%. In a case where the clustered acid catalyst has a large amount of crystallization water, typically the amount for crystallization water that is equal to or greater than the standard amount of crystallization water, the saccharide which is a product. It is dissolved in excess moisture, and the saccharide recovery ratio is decreased by mixing the saccharide to the liquid phase that includes the organic solvent solution that includes the grouped acid. By reducing the crystallization water ratio in the pooled acid catalyst to less than 100%, it is possible to prevent the saccharide from thus mixing with the pooled acid catalyst.

A method that can decrease the amount of moisture in the hydrolysis reaction mixture can be used to reduce the crystallization water ratio in the pooled acid catalyst contained in the hydrolysis reaction mixture. Examples of such a method include a method by which the sealed state of the reaction system is released and heating is effected to evaporate moisture contained in the hydrolysis mixture and a method by which a desiccant or similar agent is added to the hydrolysis mixture. The moisture contained in the hydrolysis mixture is removed.

A method for preparing the grouped acid catalyst in a grouped state will be explained below. The conversion of the pooled acid catalyst to a pooled state is increased, for example, by stirring the pooled acid in a pseudofused state, or by adding the pooled acid to a solvent and stirring under heating, or by stirring. the acid pooled together with the plant fiber material upon heating and causing the pooled acid to act as a hydrolysis catalyst. The following three specific methods can be used to increase conversion to a grouped state. (1) A method comprising a process of heating and stirring a pooled acid catalyst and an organic solvent that can dissolve the pooled acid catalyst; (2) a method by which, in a hydrolysis process in which a plant fiber material is hydrolyzed using a pooled acid catalyst, part of the plant fiber material, in an amount that can be loaded into a batch, is stirred under heating with the acid catalyst grouped in a pseudofused state and hydrolysis of the vegetable fiber material is performed; and (3) a method for heating and stirring an α-grouped acid catalyst in a pseudofused state. These methods (1) to (3) will be described below.

In method (1), which includes a process of heating and stirring a pooled acid catalyst and an organic solvent that can dissolve the pooled acid catalyst, the heating temperature may be suitably adjusted according to the change in the state of the pooled acid. in the solvent, however, usually a temperature of equal to or greater than 30 ° C is preferred. From the point of view of preventing the pooled acid catalyst from recrystallizing, it is preferred that the temperature be equal to or less than 65 ° C, in particular equal to or less than 55 ° C. Examples of organic solvents that may dissolve the pooled acid catalyst include organic solvents that may be used in the saccharide separation process described above. Among them, from the point of view of the pooled acid dissolving capacity and boiling point of an organic solvent, ethanol and methanol are preferred. The mixing ratio of the organic solvent and the pooled acid catalyst is not particularly limited and may be appropriately selected corresponding to the solubility of the pooled acid catalyst in the organic solvent. The heating and stirring time may be suitably determined corresponding to the solubility of the α-grouped acid catalyst in the organic solvent used and the heating temperature, and typically the heating and stirring time is about 10 min to about 60 min. from 30 min to 60 min. The mixing method is not particularly limited and a well known method can be used.

Even in a case where a new, unused pooled acid reagent is used, such heating and stirring of the pooled acid catalyst and organic acid may convert the pooled acid catalyst to a pooled state and inhibit the dehydration reaction of the pooled acid. saccharide in the hydrolysis process. In addition, the pooling of the reused pooled acid catalyst may be increased by adding the organic solvent to the hydrolysis and stirring reaction mixture in the saccharide separation process, and then heating and stirring the organic solvent solution including the pooled acid obtained. by solid-liquid separation. The pooled acid catalyst subjected to the pooling treatment may be separated by removing the organic solvent from the pooled acid catalyst mixture and the organic solvent after heating and stirring. In this case, by rapidly removing the organic solvent, the pooled state of the pooled acid catalyst can be easily maintained. More specifically, it is preferred that the organic solvent be removed by vacuum distillation, lyophilization, or the like. The organic solvent may also be removed by heating, but from the point of view of maintaining the grouped state of the grouped acid, it is preferred that the organic solvent be removed at a low temperature (more specifically at a temperature of equal to , or less than 65 ° C), and it may be said that the above mentioned vacuum distillation and lyophilization are preferred.

In addition, the pooling of the added pooled acid catalyst and reused pooled acid catalyst can also be increased by adding an organic solvent to a hydrolysis and stirring reaction mixture in the saccharide separation process, then adding a catalyst of Grouped acid in a crystalline state (unused pooled acid reagent or similar) to the organic solvent solution including the pooled acid obtained by solid-liquid separation, and stirring under heating. In addition to repeatedly recovering and reusing the pooled acid catalyst, even in a case where the amount of pooled acid recovered has decreased, it is possible to perform a pooling treatment of the pooled acid catalyst in a crystalline state by addition of the pooled acid catalyst. a crystalline state, and use of the saccharide separation process, thereby restoring the loss of the pooled acid catalyst in the saccharide separation process. (2) In the method by which part of the vegetable fiber material, in an amount that can be loaded in a batch, is stirred under heating with the acid catalyst grouped in a pseudofused state and hydrolysis of the vegetable fiber material is carried out in In a hydrolysis process, by hydrolyzing only part of the plant fiber material that can be loaded into a batch, it is possible to reduce the amount of monosaccharide that can be dehydrated by the acid catalyst grouped in the early stage of the hydrolysis process and to increase the grouping of the pooled acid catalyst. After the pooled acid catalyst has become the pooled state, the remaining plant fiber material is further charged, thereby making it possible to inhibit the hyperreaction of the saccharide produced from the additionally loaded plant fiber material. "Vegetable fiber material, in an amount that can be loaded in a batch" as referred to herein, is the amount that enables the mixture to become a completely homogeneous mixed and kneaded state when this amount is mixed with the catalyst of grouped acid (amount used in the hydrolysis process) in a pseudofused state, which is used in the hydrolysis process. Because the amount of vegetable fiber material that can be loaded in a batch changes depending on the type of kneading machine, this amount cannot be determined specifically, but it is generally preferred that the weight ratio (vegetable fiber material: grouped acid catalyst) of the plant fiber material in a batch-loadable quantity and the grouped acid catalyst in a pseudofused state which is used in the hydrolysis process, either 1: 2 to 1: 6. In addition, the "portion of the vegetable fiber material in a batch-loadable quantity" as referred to herein is the portion of the "vegetable fiber material in a batch-loadable quantity" mentioned above and is not limited to a specific amount. Normally, it is a very small amount, such that the viscosity of the pseudofused grouped acid catalyst prior to addition is kept uniform after this amount of the vegetable fiber material is added to, and stirred with the catalyst. acid grouped in the pseudofused state. Where such a very small amount of plant fiber material is initially added to the pooled acid catalyst that is used in the hydrolysis process, the effect of increasing the overall efficiency of the reaction can be expected, so to speak as a sacrifice. A specific amount of the "portion of the vegetable fiber material in a batch-loadable amount" is preferably equal to or less than 10% by weight, in particular equal to or less than 5%. by weight of the vegetable fiber material in an amount that can be loaded in one batch. The hydrolysis time of part of the plant fiber material is not particularly limited and can be adjusted by considering the decrease in viscosity of the hydrolysis mixture as an indicator. Typically, the hydrolysis time is about 10 min to 300 min, or 60 min to 300 min. Other conditions, such as reaction time and pressure, may be similar to those of the hydrolysis process.

By conducting hydrolysis of this portion of the plant fiber material with the pooled acid catalyst, it is possible to convert the pooled acid catalyst to a pooled state and inhibit the saccharide dehydration reaction in the hydrolysis process, while reducing the amount of dehydrated monosaccharide by the pooled acid catalyst to a minimum, even in a case where a new pooled acid reagent is used. In addition, because pooling treatment of pooled acid can be effected by using the hydrolysis process, the increased difficulty of the manufacturing process can be inhibited. Method (3) of heating and stirring the pooled acid catalyst in a pseudofused state is typically a method whereby the pooled acid catalyst is heated and brought to a pseudofused state, prior to the plant fiber material and the pooled acid catalyst. mixed in the hydrolysis process, then heating and stirring are effected. Typically, the pooled acid catalyst is converted to a pseudofused state, heated and stirred in a reaction vessel for use in the hydrolysis process and the pooling treatment is effected, and then the vegetable fiber material is added and the hydrolysis process. is effected. The heating temperature is not particularly limited as long as the pooled acid can maintain the pseudofused state, and can be appropriately adjusted according to the pooled acid type and the crystallization water ratio. In order to assemble the pooled acid catalyst with good efficiency, it is preferred that the heating be conducted at a temperature that is at least 10 to 30 ° C, more preferably at least 10 to 20 ° C, even more preferably close to at least 5 to 10 ° C higher than a temperature at which the initially pooled acid catalyst becomes the pseudofused state. The pooled acid catalyst is preferably heated and stirred with water in an amount such that the crystallization water ratio of the pooled acid catalyst becomes equal to or greater than 100%. It is especially preferred that the pooled acid catalyst be heated and stirred with water in an amount such that the crystallization water ratio of the pooled acid catalyst becomes equal to or greater than 100% the water that is. required for the hydrolysis of the vegetable fiber material in the subsequent hydrolysis process, and the water that ensures the presence of saturated water vapor in the reactor dead volume. This is because heating and stirring in the presence of water increases the transition of the pooled acid catalyst to the pseudowown state, thereby increasing the pooling. Heating and stirring time can be adjusted by considering the decrease in viscosity of the hydrolysis mixture as an indicator. Typically, the heating and stirring time may be about 60 to 300 min. The process of heating and stirring the pseudofused state acid can easily be included as a preliminary preparatory process for the hydrolysis process using the pseudofused state acid as a catalyst for hydrolysis in the existing process. In addition, the monosaccharide dehydration reaction in the hydrolysis process can be inhibited even when a new pooled acid reagent is used.

It can be determined whether the clustering of the clustered acid catalyst progressed, for example, through infrared (IR) measurements, Raman spectroscopy, nuclear magnetic resonance (NMR), and the like.

For example, in IR measurements, the determination can be made by observing a water spectrum (the aforementioned crystallization water) that is coordinated with the pooled acid and comparing the intensity of the absorption peak (in the vicinity of 3200). cm'1) derived from the crystal bound H20 molecule and an absorption peak (in the vicinity of 3500 cm'1) derived from an OH group attached to a strongly acid substrate. More specifically, when an IR spectrum of the clustered acid catalyst prior to clustering treatment and an IR spectrum of the clustered acid catalyst after clustering treatment are compared, in a case where a neighboring peak intensity 3200 cm -1 which is derived from the H20 molecule bound in a pooled acid catalyst crystal, after the pooling treatment, is smaller than that of the pooled acid catalyst, prior to the pooling treatment, and a peak intensity in the vicinity of 3500 cm -1 which is derived from an OH group bound to a strongly acidic substrate of the pooled acid catalyst after the pooling increase treatment is greater than that of the pooled acid catalyst before from the cluster increase treatment, it can be determined that the cluster has progressed. In IR measurements, the absorption peak derived from an H20 molecule is not limited to absorption from the absorption peak derived from OH groups bound to a strongly acidic substrate and can generally be observed as a broad peak.

Furthermore, in Raman spectroscopy, for example, where attention is focused on the symmetrical elongation vibrations of a phosphotungstic acid W06 octahedron, a distinct high dispersion peak is observed in the vicinity of 985 cm -1 in the catalyst. of acid grouped in a crystalline state prior to cluster treatment. However, in the pooled acid catalyst in a pooled state, after pooling treatment, a shift to a higher frequency occurs in the vicinity of 1558 cm -1, and peak intensity decreases significantly, ie sensitivity decreases. Such shifting to a higher frequency and decrease in sensitivity is caused by the structural changes described below induced by clustering of the clustered acid catalyst. In the octahedron of W06, because the ionic radius of W is as small as 0.074 nm, the spacing between W and O is extremely tight, as shown in FIG. 1. Where surface energy is stabilized by the cluster and the shape is deformed closer to the spherical shape, the symmetry of W06 decreases and the distance between W and O becomes even shorter. As a result, decreased sensitivity and increased bonding force cause simultaneous dispersion and displacement to a higher frequency. This phenomenon is not intrinsic to phosphotungstic acid and occurs similarly in other grouped acids. Therefore, the pooled state of the pooled acid catalyst can be confirmed by observing structural changes in the pooled acid catalyst by Raman spectroscopy.

EXAMPLES Quantitative determination of D - (+) - glucose and D - (+) - xylose was conducted by the high performance liquid chromatography (HPLC) postmark fluorescence detection method. The pooled acid was identified and quantitatively determined by inductively coupled plasma (ICP). EXAMPLE 1. Distilled water was placed in advance in a sealed reaction vessel (batch type; see FIG. 3), the temperature was raised to a predetermined reaction temperature (70 ° C), a saturated vapor pressure state. was obtained inside the container, and water vapor was adhered to the inner surface of the container. Then 1 kg of a heteropoly acid repeatedly used in a pooled state (the amount of crystallization water was measured in advance; phosphotungstic acid) and distilled water (35 g) in an amount representing water deficiency (excluding water of a saturated vapor pressure component at 70 ° C) relative to the sum total of the amount required to bring the heteropoly acid crystallization water to 100% and the amount of water (55.6 g) required to hydrolyze the cellulose and obtain The glucose was loaded into the container and warmed and stirred. When the temperature inside the vessel reached 70 ° C, stirring was further continued for 10 min. Then 0.5 kg of cellulose was charged and the mixture was conducted under heating at 70 ° C. Within 10 min after the heating mixture was started, the viscosity was 3 Pa.s (3000 cp). Within 1 h, the viscosity of the heated mixture decreased to 0.7 Pa.s (700 cp). Therefore, 0.5 kg of cellulose and water (55.6 g) in an amount necessary to hydrolyze the cellulose to glucose were charged and the mixture under heating at 70 ° C was continued for 2 h. Heating was then stopped, the vessel was opened, and the hydrolysis reaction mixture was cooled to room temperature while discharging the extra water vapor.

A total of 500 ml of ethanol which was twice used for washing was then added to the hydrolysis reaction mixture located within the vessel, stirring was conducted for 30 min, followed by filtration which produced a first filtrate and a first filtered material. The first filtrate (heteropoly acid ethanol solution) was recovered. A total of 500 ml of ethanol that was once used for washing was additionally added to the filtered material and stirring was conducted for 30 min, followed by filtration which yielded a second filtrate and a second filtered material. A total of 500 ml of fresh ethanol was added to the second filtered material and stirring was conducted for 30 min, followed by filtration which yielded a third filtrate and a third filtered material. Distilled water was added to the third filtrate obtained and stirring was conducted for 10 min. No residue could be confirmed to be present in the obtained aqueous solution, but the solution was still filtered and an aqueous saccharide solution was obtained. The yield of monosaccharides (a total of the sum of glucose, xylose, arabinose, mannose, and galactose) was calculated from the obtained aqueous saccharide solution. The result was 85,3%. Monosaccharide yield was calculated as follows.

Monosaccharide Yield (%): A ratio (weight ratio) of the sum total of monosaccharides actually recovered to a theoretical amount of monosaccharides produced that are produced when the entire amount of cellulose loaded is converted to monosaccharides. EXAMPLE 2. Distilled water was placed in advance in a sealed reaction vessel (batch type; see FIG. 3), the temperature was raised to a predetermined reaction temperature (70 ° C), a saturated vapor pressure state. was obtained inside the container, and water vapor was adhered to the inner surface of the container. Then, 1.15 kg of a heteropoly acid repeatedly used in a pooled state (amount of crystallization water was measured in advance; phosphotungstic acid) and distilled water (35 g) in an amount representing water deficiency (excluding saturated vapor pressure component at 70 ° C) relative to the sum total of the amount required to bring the heteropoly acid crystallization water to 100% and the amount of water (55.6 g) required to hydrolyze The cellulose and glucose obtained were loaded into the vessel and heated and stirred. When the temperature inside the vessel reached 70 ° C, stirring was further continued for 10 min. Then 0.5 kg of lignin-containing wood chips were loaded and the mixture was conducted under heating at 70 ° C. Within 10 min after the heating mixture was started, the viscosity was 3 Pa.s (3000 cp). At 3 h, lignin was removed from the heated mixture obtained using a sintered filter. The viscosity of the heated mixture from which lignin had been removed decreased to 0.7 Pa.s (700 cp). Therefore, 0.5 kg of lignin-containing wood chips and water (35 g) required to hydrolyze the cellulose contained in the glucose wood chips were loaded and mixing under heating at 70 ° C was continued for 3 h. Heating was then stopped, the vessel was opened, and the hydrolysis reaction mixture was cooled to room temperature while discharging the extra water vapor. Separation of monosaccharides and heteropoly acid was then carried out in the same manner as in Example 1. Distilled water was added to the third filtrate obtained and stirring was conducted for 10 min. A residue containing lignin was confirmed to be present in the obtained aqueous solution, and an aqueous saccharide solution was obtained by filtration. Monosaccharide yield was calculated from the aqueous saccharide solution obtained. The result was 80,2%. In this case, monosaccharide yield was calculated on the assumption that lignin removed with the sintered filter and lignin removed by filtration of the aqueous solution required 30 wt% (i.e. 300 g) of the wood used. In the present example, when lignin was removed with the sintered filter, the heteropoly acid that had been adsorbed onto lignin was removed along with lignin. This is because the amount of heteropoly acid used was by a factor 1.15 greater than that of Example 1. EXAMPLE 3. A bypass reactor (see FIG. 4), in which stirring can be performed in a heating line (constant temperature 70 ° C) relative to a main channel of heteropoly acid (phosphotungstic acid) in a pseudo-fused state. An agitation paddle 10 in the row has a structure that is effective only for agitation and virtually does not affect the transport of contents in a reaction tank 100. Therefore, the content transport speed is a sum of the sum of the component loading speeds. (heteropoly acid, plant fiber material). In reaction tank 100, a pseudofused heteropoly acid loading port 13 is on the upstream side, and a plurality of loading ports 11 (first to fourth loading port) are provided for the vegetable fiber material to be fed. downstream from loading port 13 to the heteropoly acid. Viscosity sensors 12 (first to fourth viscosity sensors) are provided downstream of the loading hole 11 to the vegetable fiber material (directly in front of the loading hole provided downstream of this loading hole or directly in front of the downstream wall of the reactor), and the viscosity of the contents within the reaction tank 100 which is determined by the viscosity sensors 12 is used to back-control the amount of vegetable fiber material loaded from the loading holes 11 to the vegetable fiber material.

The wood pits (containing lignin) were loaded from the first loading hole 11 (1), while loading into reaction tank 100 a heteropoly acid (repeatedly used in a clustered state) in a pseudo-state. molten water to which hydrolysis water was added in advance. In this case, the loading speed of the wood chips was half the loading speed of the heteropoly acid. The loading rate of the heteropoly acid and the loading speed of wood chips from the first loading hole 11 (1) were adjusted to obtain a viscosity in the first viscosity sensor 12 (1) of 0.7 Pa.s (700 cp). The loading speed of the second to fourth loading holes 11 (2) to 11 (4) was also adjusted to obtain a viscosity in the second to fourth viscosity sensors 12 (2) to 12 (4) of 0.7 Pa. .s (700 cp). The reaction mixture discharged downstream of the reactor was cooled to room temperature while removing extra water vapor. In the present example, the weight ratio of the heteropoly acid and wood chips used was 1: 12 (heteropoly acid: wood chips). The saccharides and heteropoly acid were then recovered from the hydrolysis reaction mixture in the same manner as in Example 1. Monosaccharide yield was 82.1%. In this case, monosaccharide yield was calculated under the assumption that the removed lignin required 30% by weight of the wood chips used. COMPARATIVE EXAMPLE 1. Distilled water was placed beforehand in a sealed (batch type) reaction vessel, the temperature was raised to a predetermined reaction temperature (70 ° C), a saturated vapor pressure state was obtained within the vessel. , and the water vapor was adhered to the inner surface of the container. Then 1 kg of a heteropoly acid repeatedly used in a pooled state (the amount of crystallization water was measured in advance; phosphotungstic acid) and distilled water (35 g) in an amount representing water deficiency (excluding water of a saturated vapor pressure component at 70 ° C) relative to the sum total of the amount required to bring the heteropoly acid crystallization water to 100% and the amount of water (55.6 g) required to hydrolyze the cellulose and obtain The glucose was loaded into the container and heated and stirred. Once the temperature inside the vessel reached 70 ° C, stirring was continued for 5 min. Then 0.5 kg of cellulose was charged and the mixture was conducted for 2 h under heating at 70 ° C. Heating was then discontinued, the vessel was opened, and cooling was carried out to room temperature while discharging the extra water vapor. The monosaccharides and the heteropoly acid were then recovered from the hydrolysis reaction mixture in the same manner as in Example 1. The yield of monosaccharides was 85.3%. RESULTS. Monosaccharide yield and weight ratio of heteropoly acid and fiber material obtained in Examples 1 to 3 and Comparative Example 1 are shown in Table 1.

As shown in Table 1, in Examples 1 to 3, the amount of heteropolyacid used per unit weight of the fiber material could be greatly reduced compared to that of Comparative Example 1, while maintaining monosaccharide yield. In addition, the comparison of Example 1 and Comparative Example 1 (both use a batch reactor), in Example 1, the processed amount of fiber material by heteropoly acid unit weight doubled. Therefore, the energy required for heating that is required to bring the heteropoly acid to the pseudofused state could be reduced. Furthermore, in Example 3 using a continuous reaction apparatus, the amount of heteropoly acid used could be reduced and the heating energy could also be reduced. In an industrial reaction apparatus, where water is added to the steam introduction reaction system, heating and water addition operations may be conducted simultaneously, which process is superior to the introduction of energy distilled water.

Claims (3)

Method for hydrolyzing a plant fiber material and producing and separating a saccharide including glucose, characterized in that it comprises: a hydrolysis process using a heteropoly acid catalyst grouped in a pseudofused state to hydrolyze the cellulose contained in the fiber material. plant fiber and produce glucose where, in the hydrolysis process, the pooled heteropoly acid catalyst is a first amount of the plant fiber material that increases the viscosity of the pooled heteropoly acid catalyst in a pseudofused state when added to the grouped heteropoly acid catalyst in a pseudofused state, are heated and mixed, and a second amount of the vegetable fiber material is then additionally added when the viscosity decrease of a heated mixture of the grouped heteropoly acid catalyst and the first amount of the vegetable fiber material occurs. Method according to claim 1, characterized in that a volume ratio of the first amount of plant fiber material to the grouped heteropoly acid catalyst is equal to or greater than 60%. Method according to claim 1 or 2, characterized in that a volume ratio of the second amount of the vegetable fiber material to the grouped heteropoly acid catalyst is equal to or greater than 60%,